Getting a crouton stuck in my windpipe. Your body can and will try to take over when life is on the line. Fortunately, I could still breathe a little and I had to wait for saliva to dissolve it. A scary 15 mins or so of small breathes.
When I was a small child, I put a piece of Cheerios cereal in each nostril, to "see if I could breath through the tiny holes". They got stuck, I panicked, then fell asleep. When I woke up, they were gone. I always assumed they dissolved.
Oh yeah, lungs were giving it their all to clear and they didn't care if they did a little damage to succeed. Losing some control over your body is a weird sensation. It's like someone snatching your game controller away, beating a boss, and then tossing it back into your hands.